Spin valve transducer having partly patterned magnetoresistance element

ABSTRACT

In a spin valve type transducer including two magnetic shield layers, a patterned magnetoresistance element is in direct contact with one of the magnetic shield layers. A permanent magnet layer and an electrode layer are formed on the sides of the patterned magnetoresistance element.

The present Application is a Divisional Application of U.S. patentapplication Ser. No. 09/532,444, filed on Mar. 23, 2000.

FIELD OF THE INVENTION

The present invention relates to a magnetoresistance (MR) apparatus, andmore particularly, to a spin valve type transducer capable of reducing areproducing gap to less than 0.1 μm.

As magnetic storage apparatuses have been developed in size andcapacity, highly sensitive magnetoresistive (MR) transducers (heads)have been put into practical use (see: Robert P. Hunt, “AMagnetoresistive Readout Transducer ”, IEEE Trans. on Magnetics, Vol.MAG-7, No. 1, pp. 150-154, Mar. 1971). Since use is made of theanisotropy magnetoresistance (AMR) effect of NiFe alloy, these MR headsare called AMR heads.

Recently, more highly sensitive giant magnetoresistance (GMR)transducers (heads) which are called spin valve type transducers, havealso been developed in order to achieve higher area recording density(see: Ching Tsang et al., “Design, Fabrication & Testing of Spin-ValveRead Heads for High Density Recording ”, IEEE Trans. on Magnetics, Vol.30, No. 6, pp. 3801-3806, Nov. 1994). A typical spin valve typetransducer includes a spin valve structure which is constructed by afree ferromagnetic layer, a pinned ferromagnetic layer and anon-magnetic conductive layer sandwiched by the free ferromagnetic layerand the pinned ferromagnetic layer, and a pinning ferromagnetic layerfor pinning the magnetic domain of the pinned ferromagnetic layer. Inthe spin valve type transducer, the resultant response is given by acosine of an angle between the magnetization directions of the freeferromagnetic layer and the pinned ferromagnetic layer.

A prior art spin valve type transducer is constructed by two magneticshield layers, two gap layers (magnetic isolation layers) each adheredto the inside of one of the magnetic shield layers, a spin valvestructure sandwiched by the gap layers, a permanent magnet layerprovided at the sides of the spin valve structure to provide magneticdomain control over the free ferromagnetic layer in order to suppressthe Barkhausen noise, and an electrode layer formed on the permanentmagnet layer (see JP-A-10-162322 & JP-A-10-149513). This will beexplained later in detail.

In the above-described prior art spin valve type transducer, however,since the spin valve structure is sandwiched by the two gap layers, theresolution of the transducer, i.e., a reproducing gap between the twomagnetic shield layers cannot be less than 0.1 μm, which will beexplained later.

Generally, a bit length for showing the density of bits on a medium isdenoted by the number of inversions of magnetic fluxes per inch, i.e.,kilo flux changes per inch (kFCI). For example, if the bit length is 200kFCI, one inversion length is 125 nm and one period is 250 nm.Therefore, the reproducing gap 0.1 μm (100 nm) is enough for 200 kFCI.Also, if the bit length is 400 kFCI, one inversion length is 62.5 nm andone period is 125 nm. Therefore, the reproducing gap 0.1 μm (100 nm) isalso enough for 400 kFCI. On the other hand, if the bit length is 500kFCI, one inversion length is 50 nm and one period is 100 nm, thereproducing gap 0.1 μm (100 nm) is insufficient for 500 kFCI.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a spin valve typetransducer capable of reducing a reproducing gap to less than 0.1 μm.

According to the present invention, in a spin valve type transducerincluding two magnetic shield layers, a patterned magnetoresistanceelement is in direct contact with one of the magnetic shield layers. Apermanent magnet layer and an electrode layer are formed on the sides ofthe patterned magnetoresistance element.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be more clearly understood from thedescription set forth below, as compared with the prior art, withreference to the accompanying drawings, wherein:

FIG. 1 is a cross-sectional, air bearing surface (ABS) view illustratinga prior art spin valve type transducer;

FIGS. 2A and 2B are cross-sectional views of the spin valve structure ofFIG. 1;

FIG. 3 is a cross-sectional view illustrating a modification of the spinvalve transducer of FIG. 1;

FIG. 4 is a graph showing the magnetoresistance-external field of thetransducer of FIG.3;

FIG. 5 is a cross-sectional, ABS view illustrating a first embodiment ofthe spin valve type transducer according to the present invention;

FIG. 6 is a graph showing the magnetoresistance-external field of thetransducer of FIG. 5;

FIG. 7 is a cross-sectional, ABS view illustrating a second embodimentof the spin valve type transducer according to the present invention;

FIG. 8 is a cross-sectional, ABS view illustrating a third embodiment ofthe spin valve type transducer according to the present invention;

FIG. 9 is a cross-sectional, ABS view illustrating a fourth embodimentof the spin valve type transducer according to the present invention;

FIG. 10 is a cross-sectional, ABS view illustrating a fifth embodimentof the spin valve type transducer according to the present invention;

FIGS. 11, 12, 13, 14 and 15 are cross-sectional, ABS views illustratingmodifications of the transducers of FIGS. 5, 7, 8, 9 and 10,respectively; and

FIG. 16 is a block circuit diagram illustrating a magnetic storageapparatus to which the transducer according to the present invention isapplied.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before the description of the preferred embodiments, prior art spinvalve type transducers will be explained with reference to FIGS. 1, 2A,2B and 3.

In FIG. 1, which illustrates a prior art spin valve type transducer (seeJP-A-10-162322 & JP-A-10-149513), reference numeral 1 designates asubstrate made Al₂O₃TiC which serves as a slider. Also, an about 1 μmthick lower magnetic shield layer 2 made of NiZn ferrite is deposited onthe substrate 1, and an about 30 nm thick lower gap layer (lowermagnetic isolation layer) 3 made of alumina (Al₂O₃) is deposited on thelower magnetic shield layer 2.

A spin valve structure 4 is deposited on the lower gap layer 3 by amagnetron sputtering process, a radio frequency sputtering process or anion beam sputtering process, and is patterned by an ion beam etchingprocess. The spin valve structure 4 will be explained later in detail.

Also, an about 20 nm thick permanent magnet layer 5 made of CoPt and anabout 80 nm thick electrode layer 6 made of gold (Au) are formed on thelower gap layer 3 on the sides of the spin valve structure 4.

Further, an about 50 nm thick upper gap layer (upper magnetic isolationlayer) 7 made of alumina, an about 2 μm thick upper magnetic shieldlayer 8 made of NiFe, an about 0.1 μm thick record gap layer 9 made ofalumina and an about 2 μm thick patterned magnetic pole layer 10 made ofCoFeNi are formed on the spin valve structure 4 and the electrode layer6. Also, the magnetic pole layer 10 is coated by an alumina layer 11.

Note that an exciting winding (not shown) isolated by a photoresistlayer (not shown) is formed between the upper magnetic shield layer 8and the magnetic pole layer 10.

The spin valve structure 4 of FIG. 1 is illustrated in detail in FIGS.2A and 2B.

In FIG. 2A, the spin valve structure 4 is formed by an about 3 nm thickunderlayer 41 made of Zr, an about 20 nm thick pinning layer 42 made ofantiferromagnetic material such as PtMn, an about 3 nm thick pinnedlayer 43 made of CoFe, an about 2.1 nm thick non-magnetic conductivelayer 44 made of Cu, an about 3.5 nm thick free layer 45 made offerromagnetic material such as about 0.5 nm thick CoFe and about 3 nmthick NiFe, and an about 3 nm thick protection layer 46 made of Zr.

On the other hand, in FIG. 2B, the sequence of the pinning layer 42, thepinned layer 43, the non-magnetic conductive layer 44 and the free layer45 of FIG. 2A is reversed.

In FIGS. 2A and 2B, the width of the spin valve structure 4 is about 0.4μm, and the thickness of the spin valve structure 4 is about 35 nm.

Note that the pinning layer 42 for pinning the pinned layer 43 needs tobe heat-resistant. Although PtMn is heat-resistant enough, it needs tobe thicker than about 20 nm to sufficiently exhibit antiferromagnetism.On the other hand, even if IrMn is 7 nm thick, it can exhibit excellentantiferromagnetism, however, IrMn is not heat-resistant.

As stated above, the lower gap layer 3 is made of alumina. Since aluminais deposited by a sputtering process, it cannot be thin due to thedeterioration of the insulating characteristics caused by pinholes. Inorder to suppress the generation of pinholes, the lower gap layer 3needs to be at least 30 nm thick.

On the other hand, the upper gap layer 7 is also made of alumina havinggood insulating characteristics. Besides the upper gap layer 7 needs tocover a step between the spin valve structure 4 and the electrode layer6. In this case, the electrode layer 6 needs to be 80 nm thick toachieve a high signal-to-noise (S/N) ratio, even if the electrode layer6 is made of Au. Therefore, the step between the spin valve structure 4and the electrode layer 6 is

20 nm (permanent magnet layer 5)

+80 nm (electrode layer 6)

−35 nm (spin valve structure 4)

=65 nm

In order to cover the step of 65 nm, the upper gap layer 7 needs to beat least 50 nm.

Since the resolution of a spin valve type transducer is generallydefined by a reproducing gap between the two magnetic shield layers, theresolution of the spin valve type transistor of FIG. 1 is

30 nm (lower gap layer 3)

+35 nm (spin valve structure 4)

+50 nm (upper gap layer 7)

=115 nm

Note that, even if the pinning layer 42 is made of 7 nm thick IrMn, thereproducing gap is 102 nm.

Thus, in the spin valve type transducer of FIG. 1, it is impossible toreduce the reproducing gap to less than 0.1 μm.

In FIG. 3, which is a modification of the spin valve type transducer ofFIG. 1, the lower magnetic shield layer 2 of FIG. 1 is replaced by aninsulating lower magnetic shield layer 2′, and the lower gap layer 3 ofFIG. 1 is omitted. Therefore, the resolution of the spin valve typetransducer of FIG. 3 is

35 nm (spin valve structure 4)

+50 nm (upper gap layer 7)

=85 nm

Thus, it is possible to reduce the reproducing gap less than 0.1 μm.

In the spin valve type transducer of FIG. 3, however, since a gap layer(magnetic isolation layer) is not provided between the permanent magnetlayer 5 and the insulating lower magnetic shield layer 2′, the magneticlines of force generated from the permanent magnet layer 5 is leakedinto the insulating lower magnetic shield layer 2′, so that the magneticdomain of the free layer 45 of the spin valve structure 4 cannot besufficiently controlled by the permanent magnet layer 5. As a result, alarge hysteresis is created in a magnetoresistance and magnetic field(R-H) loop as shown in FIG. 4, which also increases wiggled waveformsdue to the Baukhausen noise in regenerated signals.

In FIG. 5, which illustrates a first embodiment of the presentinvention, an about 10 nm thick magnetic isolation layer 3A made of Cris provided only between the permanent magnet layer 5 and the lowermagnetic shield layer 2 instead of the lower gap layer 3 of FIG. 1.Note, that the thickness of the magnetic isolation layer 3A can bebetween 1 nm and 100 nm. That is, the spin valve structure 4 is indirect contact with the lower magnetic shield layer 2. Also, the spinvalve structure 4 has the same configuration as illustrated in FIG. 2A.Note that the upper gap layer 7 is made about 55 nm thick, since theelectrode layer 6 is made about 25 nm thick and a step between the spinvalve structure 4 and the electrode layer 6 is a little larger.Therefore, the resolution of the spin valve type transducer of FIG. 5 is

35 nm (spin valve structure 4)

+55 nm (upper gap layer 7)

=90 nm

Thus, it is possible to reduce the reproducing gap to less than 0.1 μm.

In the spin valve type transducer of FIG. 5, since the magneticisolation layer 3A is provided between the permanent magnet layer 5 andthe insulating lower magnetic shield layer 2, the magnetic lines offorce generated from the permanent magnet layer 5 hardly leak into thelower magnetic shield layer 2, so that the magnetic domain of the freelayer 45 of the spin valve structure 4 can be sufficiently controlled bythe permanent magnet layer 5. As a result, no large hysteresis iscreated in a magnetoresistance and magnetic field (R-H) loop as shown inFIG. 6, which also decreases wiggled waveforms due to the Baukhausennoise in regenerated signals.

In FIG. 7, which illustrates a second embodiment of the presentinvention, a spin valve structure 4A is provided instead of the spinvalve structure 4 of FIG. 1. The spin valve structure 4A has the sameconfiguration as illustrated in FIG. 2A except that the width of thefree layer 45 and the protection layer 46 is about 0.3 μm while thewidth of the underlayer 41, the pinning layer 42, the pinned layer 43and the non-magnetic conductive layer 44 is the same as that of thelower magnetic shield layer 2 and the substrate 1. Therefore, theunderlayer 41, the pinning layer 42, the pinned layer 43 and thenon-magnetic conductive layer 44 serve as the lower gap layer 3 of FIG.1. In this case, the spin valve structure 4A is in direct contact withthe lower magnetic shield layer 2, and therefore, the resolution of thespin valve type transducer of FIG. 7 is

35 nm (spin valve structure 4)

+50 nm (upper gap layer 7)

=85 nm

Thus, it is possible to reduce the reproducing gap to less than 0.1 μm.

In the spin valve type transducer of FIG. 7, since the non-magneticconductive layer 44 is provided between the permanent magnet layer 5 andthe lower magnetic shield layer 2, the magnetic lines of force generatedfrom the permanent magnet layer 5 hardly leak into the lower magneticshield layer 2, so that the magnetic domain of the free layer 45 of thespin valve structure 4A can be sufficiently controlled by the permanentmagnet layer 5. As a result, no large hysteresis is created in amagnetoresistance and magnetic field (R-H) loop as shown in FIG. 6,which also decreases wiggled waveforms due to the Baukhausen noise inregenerated signals.

In FIG. 8, which illustrates a third embodiment of the presentinvention, the spin valve structure 4 has the same configuration asillustrated in FIG. 2B. Also, the electrode layer 7 is about 90 nmthick. Further, the upper gap layer 7 of FIG. 1 is not provided, so thatthe spin valve structure 4 is in direct contact with the upper magneticshield layer 8. Therefore, the resolution of the spin valve typetransducer of FIG. 8 is

30 nm (lower gap layer 3)

+35 nm (spin valve structure 4)

=65 nm

Thus, it is possible to reduce the reproducing gap to less than 0.1 μm.

In the spin valve type transducer of FIG. 8, since the lower gap layer 3is provided between the permanent magnet layer 5 and the lower magneticshield layer 2, the magnetic lines of force generated from the permanentmagnet layer 5 hardly leak into the lower magnetic shield layer 2, sothat the magnetic domain of the free layer 45 of the spin valvestructure 4 can be sufficiently controlled by the permanent magnet layer5. As a result, no large hysteresis is created in a magnetoresistanceand magnetic field (R-H) loop as shown in FIG. 6, which also decreaseswiggled waveforms due to the Baukhausen noise in regenerated signals.Note that the magnetic lines of force generated from the permanentmagnet layer 5 toward the upper magnetic shield layer 8 are stopped bythe thin electrode layer 7.

In FIG. 9, which illustrates a fourth embodiment of the presentinvention, the first embodiment as illustrated in FIG. 5 is combinedwith the third embodiment as illustrated in FIG. 8. That is, an about 5nm thick magnetic isolation layer 3A made of Cr is provided only betweenthe permanent magnet layer 5 and the lower magnetic shield layer 2instead of the lower gap layer 3 of FIG. 1. As a result, the spin valvestructure 4 is in direct contact with the lower magnetic shield layer 2.In this case, the spin valve structure 4 has the same configuration asillustrated in FIG. 2A. On the other hand, the upper gap layer 7 of FIG.1 is not provided, so that the spin valve structure 4 is in directcontact with the upper magnetic layer 8.

In FIG. 5, the free layer 45 is on the lower side of the reproducinggap. In view of the sensitivity, it is preferable that the free layer 45be in the center of the reproducing gap. Therefore, in FIG. 9, in orderto locate the free layer 45 in the center of the reproducing gap, thethickness of the layers are made as follows:

underlayer 41: 3 nm

pinning layer 42: 20 nm

pinned layer 43: 2 nm

non-magnetic conductive layer 44: 2.1 nm

free layer 45: 2.5 nm (0.5 nm CoFe/2 nm NiFe)

protection layer 46: 27 nm

In this case, the reproducing gap is 57 nm. Therefore, the resolution ofthe spin valve type transducer of FIG. 9 is

57 nm (spin valve structure 4)

=57 nm

Thus, it is possible to reduce the reproducing gap to less than 0.1 μm.

In the spin valve type transducer of FIG. 9, since the magneticisolation layer 3A is provided between the permanent magnet layer 5 andthe insulating lower magnetic shield layer 2, the magnetic lines offorce generated from the permanent magnet layer 5 hardly leak into thelower magnetic shield layer 2, so that the magnetic domain of the freelayer 45 of the spin valve structure 4 can be sufficiently controlled bythe permanent magnet layer 5. As a result, no large hysteresis iscreated in a magnetoresistance and magnetic field (R-H) loop as shown inFIG. 6, which also decreases wiggled waveforms due to the Baukhausennoise in regenerated signals.

In FIG. 10, which illustrates a fifth embodiment of the presentinvention, the second embodiment as illustrated in FIG. 7 is combinedwith the third embodiment as illustrated in FIG. 8. That is, the spinvalve structure 4A of FIG. 7 is provided instead of the spin valve 4 ofFIG. 1. As a result, the spin valve structure 4A is in direct contactwith the lower magnetic shield layer 2. On the other hand, the upper gaplayer 7 of FIG. 1 is not provided, so that the spin valve structure 4 isin direct contact with the upper magnetic layer 8.

Even in FIG. 10, in order to locate the free layer 45 in the center ofthe reproducing gap to improve the sensitivity, the thickness of thelayers are made as follows:

underlayer 41: 3 nm

pinning layer 42: 20 nm

pinned layer 43: 2 nm

non-magnetic conductive layer 44: 2.1 nm

free layer 45: 2.5 nm (0.5 nm CoFe/2 nm NiFe)

protection layer 46: 27 nm

In this case, the reproducing gap is 57 nm. Therefore, the resolution ofthe spin valve type transducer of FIG. 10 is

57 nm (spin valve structure 4)

=57 nm

Thus, it is possible to reduce the reproducing gap to less than 0.1 μm.

In the spin valve type transducer of FIG. 10, since the non-magneticconductive layer 44 is provided between the permanent magnet layer 5 andthe insulating lower magnetic shield layer 2, the magnetic lines offorce generated from the permanent magnet layer 5 hardly leak into thelower magnetic shield layer 2, so that the magnetic domain of the freelayer 45 of the spin valve structure 4 can be sufficiently controlled bythe permanent magnet layer 5. As a result, no large hysteresis iscreated in a magnetoresistance and magnetic field (R-H) loop as shown inFIG. 6, which also decreases wiggled waveforms due to the Baukhausennoise in regenerated signals.

In the transducers of FIGS. 9 and 10, the thickness of the layers can bemade as follows:

underlayer 41: 3 nm

pinning layer 42: 15 nm

pinned layer 43: 2 nm

non-magnetic conductive layer 44: 2.1 nm free layer 45: 2.5 nm (0.5 nmCoFe/2 nm NiFe) protection layer 46: 22 nm

In this case, the reproducing gap is 47 nm. Therefore, in this case, theresolution of the spin valve type transducer of FIGS. 9 and 10 is

47 nm (spin valve structure 4)

=47 nm

Thus, it is possible to reduce the reproducing gap less than 0.05 μm,which is sufficient for 1000 kFCI where one inversion length is 25 nmand one period is 50 nm.

In FIGS. 11, 12, 13, 14 and 15, which illustrate modifications of thetransducers of FIGS. 5, 7, 8, 9 and 10, respectively, a NiZn ferritesubstrate 2A is provided instead of the Al₂O₃?TiC substrate 1 and theNiZn ferrite lower magnetic shield layer 2, thus reducing themanufacturing cost.

The method for manufacturing the transducer of FIG. 5 is explainedbelow.

First, an about 1 μm thick lower magnetic shield layer 2 made of NiZnferrite is deposited on a substrate 1 made of Al₂O₃TiC. Note that othersoft magnetic ferrite materials can be used instead of NiZn ferrite.

Next, a spin valve structure 4 is deposited on the lower magnetic shieldlayer 2 by a magnetron sputtering process, a radio frequency sputteringprocess or an ion beam sputtering process. That is, an about 3 nm thickunderlayer 41 made of Zr, an about 20 nm thick pinning layer 42 made ofPtMn, an about 3 nm thick pinned layer 43 made of CoFe, an about 2.1 nmthick non-magnetic conductive layer 44 made of Cu, an about 3.5 nm thickfree layer 45 made of about 0.5 nm thick CoFe and about 30 nm thickNiFe, and an about 3 nm thick protection layer 46 made of Zr aresequentially deposited on the lower magnetic shield layer 2.

Next, a photoresist pattern (not shown) is formed on the spin valvestructure 4. Then, the spin valve structure 4 is patterned by an ionbeam etching process using the photoresist pattern as a mask. As aresult, the spin valve structure 4 is mesa-shaped due to the small ionbeam scattering phenomenon.

Next, an about 10 nm thick magnetic gap layer (magnetic isolation layer)3A made of Cr, an about 25 nm thick permanent magnet layer 5 made ofCoPt and an about 80 nm thick electrode layer 6 made of Au aresequentially deposited on the entire surface by an ion beam sputteringprocess using an Ar gas pressure of about 1.33×10⁻³ Pa (1×10⁻⁵ Torr)where the distance between the center of each target and a waferrotating at 10 rpm is 25 cm. In this case, since the Ar gas pressure islower as compared with the other sputtering process where the Ar gaspressure is usually 1.33×10⁻² Pa (1×10⁻⁴ Torr), the scattering effect ofparticles caused by the Ar gas can be small. Also, since the distancebetween each target and the wafer is large, the direction of particlesdeposited on the wafer can be uniform. Further, since no plasma gas ispresent on the surface of the wafer in the ion beam sputtering process,the photoresist pattern is not heated, so that the photoresist patternis not deformed. Then, the photoresist pattern is lifted off.

Next, an about 55 nm thick upper gap layer 7 made of alumina isdeposited on the entire surface by a sputtering process. Then, an about2 μm thick upper magnetic shield layer 8 made of NiFe and an about 0.1μm thick record gap layer 9 made of alumina are sequentially deposited.Then, an about 2 μm thick magnetic pole layer 10 made of CoFeNi isformed by a plating process and is patterned. Then, an alumina layer 11is coated.

When manufacturing the transducers of FIGS. 7, 10, 12 and 15, the spinvalve structure 4 is etched by using the non-magnetic conductive layer44 as a stopper. Also, the upper magnetic shield layer 8 is formedwithout the formation of the upper gap layer 7.

When manufacturing the transducers of FIGS. 8, 9, 10, 13, 14 and 15, theupper magnetic shield layer 8 is formed with the formation of the uppergap layer 7.

When manufacturing the transducers of FIGS. 11, 12, 13, 14 and 15, thelower magnetic shield layer 2 is not formed, and the spin valvestructure 4 or 4A is formed directly on a NiZn ferrite substrate 2A.

The transducer according to the present invention is applied to amagnetic storage apparatus as illustrated in FIG. 16. In FIG. 16, amagnetic white/read head 1601 including the transducer according to thepresent invention faces a magnetic medium 1602 rotated by a motor 1603.The magnetic write/read head 1601 is coupled via a suspension 1602 to anarm 1603 driven by a voice coil motor 1606. Thus, the magneticwrite/read head 1601 is tracked by the voice coil motor 1606 on themagnetic medium 1602. The magnetic write/read head 1602 is controlled bya write/read control circuit 1607. Also, the motor 1603, the voice coilmotor 1606 and the write/read control circuit 1607 are controlled by acontrol unit 1608. As explained above, the transducer according to thepresent invention can have a reproducing gap of less than 0.1 μm for 500kFCI, if the coercive force of the magnetic medium 1602 is more than276.5 kA/m (3500 Oe) and the distance between the head 1601 and themagnetic medium 1602 is less than 30 nm, the magnetic storage apparatusof FIG. 16 can have a storage capacity of more than 40 Gbits per squareinch.

According to the present invention, the reproducing gap of a spin valvetype transducer can be less than 0.1 μm for 500 kFCI.

What is claimed is:
 1. A spin valve transducer comprising: first andsecond magnetic shield layers; a patterned magnetoresistance element indirect contact with said first shield layer; a magnetic isolation layerformed on sides of said patterned magnetoresistance element in directcontact with said first magnetic shield layer; and a permanent magnetlayer formed on said magnetic isolation layer; wherein said patternedmagnetoresistance element comprises: a pinning layer comprisingantiferromagnetic material; a pinned layer comprising ferromagneticmaterial adhered to said pinning layer; a free layer comprisingferromagnetic material; and a non-magnetic conductive layer sandwichedby said pinned layer and said free layer; said free layer comprising asingle magnetic domain controlled by said permanent magnet layer.
 2. Aspin valve transducer comprising: first and second magnetic shieldlayers; a magnetoresistance element including a patterned portion and anon-patterned portion in direct contact with said first magnetic shieldlayer; and a permanent magnet layer formed on said non-patterned portionof said magnetoresistance element, said patterned portion of saidmagnetoresistance element comprising at least a free layer made offerromagnetic material.
 3. A spin valve transducer comprising: first andsecond magnetic shield layers; a magnetoresistance element including apatterned portion and a non-patterned portion in direct contact withsaid first magnetic shield layer; and a permanent magnet layer formed onsaid non-patterned portion of said magnetoresistance element; anelectrode layer formed on said permanent magnet layer; and a gap layerinterposed between said patterned portion of said magnetoresistanceelement and said second magnetic shield layer and between said electrodelayer and said second magnetic shield layer.
 4. The transducer as setforth in claim 2, wherein said second magnetic shield layer is in directcontact with said patterned portion of said magnetoresistance elementand said electrode layer.
 5. The transducer as set forth in claim 2,wherein said first magnetic shield layer comprises insulating material.6. The transducer as set forth in claim 2, wherein a reproducing gapbetween said first and second magnetic shield layers is less than 0.1μm.
 7. The transducer as set forth in claim 2, further comprising anon-magnetic insulating substrate on which said first magnetic shieldlayer is formed.
 8. The transducer as set forth in claim 7, wherein saidfirst magnetic shield layer comprises a soft-magnetic ferrite.
 9. Thetransducer as set forth in claim 2, wherein said first magnetic shieldlayer comprises a non-magnetic substrate.
 10. The transducer as setforth in claim 2, wherein said first magnetic shield layer comprises aninsulating substrate comprising a soft magnetic ferrite.
 11. A spinvalve transducer comprising: two magnetic shield layers; amagnetoresistance element in direct contact with one of said two shieldlayers; and a permanent magnet layer formed on sides of saidmagnetoresistance element, wherein said magnetoresistance elementcomprises a patterned portion connected to ends of said permanent magnetlayer and a non-patterned portion interposed between said one of saidmagnetic shield layers and said permanent magnet layer, wherein saidmagnetoresistance element comprises: a pinning layer comprisingantiferromagnetic material; a pinned layer comprising ferromagneticmaterial adhered to said pinning layer; a free layer comprisingferromagnetic material; and a non-magnetic conductive layer sandwichedby said pinned layer and said free layer, said patterned portion beingformed by said free layer, said non-patterned portion being formed bysaid pinning layer, said pinned layer and said non-magnetic conductivelayer.